<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <script src="./js/test.js" defer></script>
    <script>
        console.log('我不加defer属性');
        window.addEventListener('DOMContentLoaded', () => {
            console.log("defer中的代码要在这个事件执行之前执行");
        })
    </script>
    <div>1</div>
    <div>2</div>
    <div>3</div>
    <div>4</div>
    <div>5</div>
</body>

</html>